A hypervisor that is a virtualization program generates a plurality of virtual machines on a physical machine. By having a plurality of users use the plurality of virtual machines generated on the physical machine, the physical machine is efficiently utilized. The physical machine is a computer or an information processing device.
In an information processing system that generates a plurality of virtual machines on a physical machine, a virtual machine may be added to a physical machine or a virtual machine generated on a physical machine may be relocated to another physical machine. In such cases, it is needed to estimate a load on a physical machine due to an operation of a virtual machine such as a CPU load (or CPU usage, a processor load, or processor usage).
A CPU load of a virtual machine includes a load for processing by the virtual machine and a load for I/O data transmission. The CPU load for I/O data transmission is a load based on processing of a virtual switch by a hypervisor between a virtual network interface (hereinafter, referred to as a virtual NIC (Network Interface Card)) of a virtual machine and a physical network interface (hereinafter, referred to as a physical NIC). The CPU load for I/O data transmission is normally estimated based on an I/O data transmission amount of a virtual NIC of a virtual machine.
Estimation of a load of a virtual machine is described in Japanese Patent Application Laid-open No. 2009-123174, Japanese Patent Application Laid-open No. 2011-258098, and Japanese Patent Application Laid-open No. 2009-239374.